Contributing to Zombie
The zombieverter is an open source project and thus contributions to code and features are welcome. That said some caution should be used when setting yourself up to modify and contribute to the Zombie source code. There are interwoven functions so any changes made should be thoroughly tested on the bench if possible before used in a vehicle to avoid any unexpected outcomes. Any changes to the source code are done so at your own risk.
Making changes and creating pull requests
It is best practice to base any changes from the last release version of the source code. From here you should create your own branch on github for each specific function/bug fix that has been applied and verified working.
A pull request should then be applied to the testing branch for verification before it is added to the master branch on the next firmware release.